Emergency release of power-drive drawer



April 18, 1961 J. E. MARTENS EMERGENCY RELEASE OF POWER-DRIVE DRAWERFiled Oct. 20, 1958 2 Sheets-Sheet 1 JA CK E. MARTENS ATTORNEYS April18, 1961 J. E. MARTENS EMERGENCY RELEASE OF POWER-DRIVE DRAWER FiledOct. 20, 1958 2 Sheets-Sheet 2 INVENTOR. JACK E. MARTENS ATTORNEYPatented Apr. 18, 1961 EMERGENCY RELEASE OF POWER-DRIVE DRAWER Jack E.Martens, .Gary, Ind., assignor to The Anderson Company, a corporation ofIndiana Filed Oct. 20, 19ss,ser. No. 768,329

9 Claims. (31. 74 -4248) This invention relates to a motion-transmittingdevice and more particularly with such a device having a releasemechanism for disengaging the device.-

This invention pertains to a power-driven mechanism for shifting acarriage, such as an automobile seat or window, truck tailboard, garagedoor, machine table or the like. For the purpose of illustration theinvention is shown as used for sliding to an accessible position, andretracting, a drawer or tray of a frozen-food locker or refrigerator. 7

The primary object of the invention is to provide an arrangement bywhich, in the event of power failure or mechanical difliculty, thedrawer or other device may be readily opened or closed manually, withoutmaterial hindrance from said mechanism.

According to the forms of the invention shown, a drawer or carriage isshifted by means of a threaded shaft, one end of the shaft beingconnected to-exert a push or pull upon the drawer. Readily releasablemeans is provided for normally latching the shaft against rota tion. Amotor-driven antifriction motion-transmitting nut assembly is threadedupon said shaft, while held against travel therealong, thus causing theshaft to move along its axis when the nut assembly is driven. Foraccomplishing the object indicated, nut assemblies available under thetrademark Roton, a product of The Anderson Company, Gary, Indiana,present the peculiarly desirable quality of extremely low frictionaldrag. If either the shaft or the Roton-type nut is free to turn, as byreleasing the latch above mentioned, thenmanually pushing upon thehandle of the drawer will readily pass the shaft through the Roton-typenut, substantially untrammeled.

Additional objects and attributes of the invention will become evidentwhen the description hereinafter set forth is considered in conjunctionwith-the drawings annexted hereto.

In the drawings:

Figure 1 is a side view showing the application of the invention to adrawer of a foodlocker or refrigerator,

portion of the latter being shown in section;

Figure 2 is an enlarged view taken on line 2--2 of Figure 3 showing indetail the shaft andmotion transmitting nut arrangement; l

Figure 3 is a front view showing the motor: drive a drawer mounted in anopening formed in the casing, to be slid or rolled outward, as shown indotted lines, to a position Where its contents are accessible, andthereafter returned to its normal storage position within the casing.Drawer 13 includes a front wall 14 somewhat larger than the opening forthe drawer, and this front end wall is provided with a handle 15. Theusual combined seal and insulation material 16 is provided for engagingthe periphery of the front wall 14 of the drawer.

The framework 12 is designed to provide space for the power-operatedmechanism which is normally to advance and retract drawer 13. Thismechanism includes a threaded shaft 17, and a power-driven antifrictionnut assembly 18 engaging the threads of said shaft, the nut assemblybeing restrained from moving axially of the shaft. One end 19 of theshaft 17 is connected to a bracket 20, which bracket in turn is securedby screws 21 to the lower edge of the front 14 of the drawer 13. Areleasable latch device 22, carried by bracket 20, normally restrainsshaft 17 against rotation. Thus, upon rotation of the nut assembly 18,shaft 17 will be moved axially to advance or retract the drawer.

connection to the motion-transmitting nut, and one means of locking thethreaded shaft against'rotation;

Figure 4 is a detail of the. shaft locking device of Figure 3, showingthe manner in which the shaft applies thrust to the drawer;

Figure 5 is a view corresponding to 'Figure 2, but illustratinga-modification of the means for restraining the shaft against rotation;

Figure 6 is a detail view of the restraining means'of Figure 5, inopened or released position; and

Figure 7 is aview taken on line 77ffof Figurej 5,

looking in'the direction of the arrows.

Referring more particularly to -the drawingsfwherein similarreferencenumerals refer to similar parts through out the several views,and specifically referring toqF ig "ures l4, 10 designates a portion ofarlocker or refrigera- Y tor casing, supported'upon aframework12,andfE13;is'

- bearing 23 to prevent axial movement of the nut assembly. The outerrace 26 of the bearing is supported from frame 12 bya pair of arcuateclamp arms 27, partially encircling the outer race (Figure 3). Eachclamp arm 27 in turn is attached to frame 12 by bolt means 28.

A pulley 29 is secured to an extension 30 of ring element 24 of the nutassembly. The pulley 29 is driven from reversible electric motor 31,also mounted on frame 12, through belt 32. It is manifest that motor 31is to be controlled from suitably placed switch means, not shown.

As alluded to above, the inverted U-shaped bracket 20 is secured to thedrawer and has an opening 33 in the inner leg 33 through which the endportion 19 of shaft 17 extends. The end 34 of shaft 17 is shown as 7pointed to reduce friction with the point abutting the outer leg 35 ofbracket 29. A pin 36 passes through and is fixed in an opening providedin the end portion 19 of shaft 17 with the overhanging end portions ofthe pin engaging the inner face of the latch device 22, which in turnbears against the-inner 'wall of leg 33 of bracket 20. 4

Latch device 22 is shown as a plate slidably mounted on leg 33 ofbracket 20 by means of a headed shoulder pin 37, which pin passesthrough slot 38 formed in the latch and is threaded or riveted forengagement with leg 393 of the bracket. Abutments 39 are provided nearone end of plate 22 adapted to be brought into engagement with the endportions of pin 36 to lock-shaft 17 against rotation. The opposite endof plate22 isformed with a ledge or finger grip 40 to facilitate slidingplate 22 into and out of locking relation with respect to pin 36 ofshaft 17. a

Av tubular protective member 41 extends over and along shaft 17. Theends of member 41 are rigidly supported on the locker casing-10 by means"of-support shaft 17 on .the drawer, as will appear hereinafter.@Abilfment 43 is provided with a raised bearing portion'46 "en assemblyls; These'abutmentsam designed to engage cage member 45 0f the nut18"and s'top the thrust of gaging the inner wall'of tubular member "4-1to ."steady' jthefree end offshaft 17, whilepermitting both rotary and"a fi ov'ement of shaft'17 within said member 4 1; l g

A nut assembly of the type disclosed by US. Patent No. 2,714,005, orvariants thereof, available under the trademark Roton is peculiarlyuseful in the present organization. The form of Roton-type not shown inFigure 2, as mentioned above, includes a tubular ring element 24,secured to the inner race 25 of bearing 23 to restrain said elementagainst axial movement. The interior of element 24 is formed with anintermediate portion 47 of reduced internal diameter, providing a pairof oppositely facing raceways or abutments therein, facing the oppositeenlarged ends 43 of ring element 24.

A plurality of bearing elements 49 are interposed between the threads ofshaft member 17 and raceways 47 of ring member 24 to adapt these membersfor relative rotational and endwise movement and to transfer or transmitthe motion and load or force from one member to the other. The bearingelements 49 are preferably of'the type wherein at least two generallytoroidal hearing surfaces are axially spaced a distance corresponding tothe width of portion 47 of member 24, so that the bearing surfaces ofelements 49 are positioned in contact with the raceways formed byportion 47. Loosely positioned about the threaded shaft 17, within thering 24, is the tubular cage member or carrier 45, which has openingswithin which are nested the bearing elements 49.

Rotation of nut assembly lti in either direction rotates the bearingelements 49 about their own axes and also planetates them about the axisof the shaft 17. The planetation causes the bearing elements 49 to rollup or down the spiral surfaces of shaft 17 depending upon the directionof rotation of motor 49. Since the nut assembly 18 is not permitted tomove along the shaft 17, and the shaft is normally locked againstrotation, the rotary action of nut assembly 18 imparts an axial movementto shaft 17.

It should be understood that, when either abutment 43 or 44- of shaft 17engages cage 45 of the nut assembly, planetation will cease and ring 24will idly spin upon bearing elements 49, without effecting materialthrust on shaft 17. By disposing the abutments 43 and 44 at positionscorresponding to limits of travel desired for drawer 13, opening orclosing movement of the drawer will stop at such set positions, eventhough motor 3%) continues to run. It is clear, therefore, that thearrange ment disclosed avoids the use of motor controls which otherwisewould be necessary to prevent strain and jamming of the apparatus.

By reason of the extremely low frictional characteristics and otherfeatures of design of nut assembly 18, should either the nut assembly orthe shaft 17 be free to rotate, thenshaft 17 may be readily movedthrough the nut assembly in either direction. Thus, in case of powerfailure or mechanical difliculty, by simply sliding latch 22 to theright (Figure 3) to release shaft 17 for rotation, the drawer may beopened or closed untrammeled by the power-operated mechanism. This iparticularly useful in the event the power fails with the drawer open,whereupon to close the drawer the latch 22 is released and pressure isapplied to the drawer so that a force is exerted between leg 35 and thepointed end 24 of the shaft 17 such that the shaft will rotate freelyabout its axis through the nut 18 until the drawer is closed.

Opening the drawer with the power off is extremely easy since the pin 36passes through the opening 33' in the leg 33 of the bracket 29 of thedrawer. The drawer is completely-free of the'shaft 17 and nut 18 as thedrawer is opened. a

in the modification or Figures 57, parts identical with those of thefirst form of the invention are designated I by the same referencecharacters.- A nut assembly 50 is shown mounted in a sleeve 51, whichsleeve is snugly fitted into an opening in'holder 52. Holder 52 in turn7 is supported on frame 12 by a metal stamping 53, which stamping 53 byscrews 55, or in any other conventional manner. A portion of stamping 53diametrically opposite clamping bolt 54 is formed with an extension 56received in a rubber block 57, secured to the locker or refrigeratorcasing 10 by metal holder 58. It will be observed that stamping 53 isformed with a central sleeve portion 59 in which an end of tubularmember 41 is received and sustained. Further, stamping 53 prevents thenut assembly 50 from moving toward the left (Figure 5)., while movementin the opposite direction is restrained by engagement of flange 69 ofring 24 with sleeve 51.

Pulley 62, in this modification, has been given a cup shape to effectcompactness and to apply the radial load of the belt 32 centrally ofring 24.

The latch and thrust connections of shaft 17 to drawer 13 include anL-shaped bracket 64, having one leg attached by screw 66 to front wall14 of the drawer. Latch 67, for securing shaft 17 against rotation andtransmitting its thrust to drawer 14, is carriedby the depending portion65 of the bracket. Latch 67 consists of a Ushaped spring having the ends68 of each of its legs 69 inwardly and reversely curved into asubstantially semi-circular shape. The bight 70 of the latch spring 6'7is secured to bracket 65 by a pair of vibration-damping connectors 71.Shaft 17 is formed adjacent its pointed end 24 with a taperedcircumferential groove 72 adapted to receive the inturned ends 68 of thelegs 69 of spring 67. I

A combined clamp and thrust plate 74 extends through and beyond matchingopenings 75 formed in legs 69 of spring latch 67. One end of plate 74 isformed with lugs 76 to prevent the plate 74 from being drawn entirelythrough leg 65 while the other end of plate 74 is provided with a camarm 77, having a finger grip 78. Cam arm 77 has two cam surfaces 759 and80 which are located different distances away from the center of thepivot 81 between the cam arm 77 and the plate 74. The cam surface 79 islocated a greater distance from the center of the pivot 81 and, when inengagement with the lower leg 69 of latch 67, holds the lugs 76 on theplate 74 into engagement with the other leg 69 of the latch 67 to lockthe ends 6S of the latch into operative engagement with the groove 72 onthe end 34 of the shaft 17. Rotation of the cam arm 77 about the pivot81 serves to release the ends 68 of spring legs 69 from engagement withthe shoulder of groove 72 of shaft 17, at once releasing shaft 17 forrotation so that it becomes a simple matter to close the drawer whenshaft 17 rotates freely in the nut 50. The central portion of plate 74is formed with a recess 82 to receive the pointed end 24 of shaft 17 soas to reduce to a minimum the friction between the shaft 17 and theplate 74. r

The combined shaft-to-bracket thrust connection and latch of Figures5-7, aside from its simplicity, presents the highly desirable featurethat the drawer 13 may be disconnected from shaft 17 in toto whenthepower fails with the drawer closed. I Thus, in the event that powerfailure'occurs when drawer 13 is closed, then, by operating cam arm 71andreleasing the shaft 17 from restraint, the power means is completelydivorced from the drawer. The drawer can now be manually opened andclosed as though there were no operating mecha-' nism employed in theapparatus. 7 Should the power failure occur while the draweris'open, thecam arm. 77 is moved to the disengaged position and the drawer is closedby pushing thereon. The result is that the screw 17 rotates about itsaxis and spins right through the nut asscm 1y. The drawer whendisconnected from the shaft "will operate in the manual "phase, both inopening and in closing, entirelyindependent of the power mechanism.

' Having thus described my' invention, it is obviousthat variousmodifications-may be made in the same without departing from the spiritof the invention; and, therefore,

I do not wish to be understood as limiting myself to the exact forms,constructions, arrangements and combinations of parts herein shown anddescribed.

I claim:

1. Power mechanism for operating a reciprocably mounted carriagecomprising driving and driven units,

. one of said units being a threaded shaft, the other unit being amotion-transmitting nut assembly cooperating with said shaft, one ofsaid units being operatively connected with the carriage to movetherewith and to move the carriage axially of said units, the other unitbeing fixed against axial movement, power means for driving one of saidunits, and manually operable readily releasable means normallypreventing rotation of the other unit with respect to said carriage.

2. Mechanism for operating a carriage back and forth comprising athreaded shaft, an antifriction nut assembly cooperating with thethreads of said shaft, said assembly being fixed against movement alongsaid shaft, said assembly comprising a ring having races formed thereinspaced according to the threads of said shaft, bearing elements eachhaving spaced thread and race engaging portions, a tubular cage withinsaid ring and having apertures receiving said bearing elements, one endof said shaft being connected with said carriage to move the same ineither direction, means releasably latching said shaft against rotation,and reversible power means for rotating said nut assembly.

3. A closure operator comprising a threaded shaft having one endconnected to said closure to apply a force thereto, an antifriction nutassembly threadedly engaging said shaft, means mounting said nutassembly for rotation while restraining the assembly against movementaxially of said shaft, the nut assembly substantially supporting saidshaft, a tubular member mounted to receive the free end of said shaft,abutment means fixed to said shaft on either side of said nut assembly,the abutment within said tubular member including a head engaging saidtubular member to steady the free end of said shaft, a reversible motoroperatively connected to rotate said nut assembly, and releasable meansfor latching said shaft against rotation.

4. Means for operating a carriage comprising a frame, an antifrictionnut assembly rotatably mounted on said frame while restrained from axialmovement, reversible motor means operatively connected to a member ofsaid nut assembly to rotate the same, a threaded shaft extending throughsaid assembly in threaded engagement therewith and supported thereby,plate means rigid with said carriage, one end of said shaft beingprovided with means connected to said plate means to exert a push orpull on said carriage depending upon the direction of rotation of saidnut assembly, and releasable latch means normally locking said shaftagainst rotation.

5. Means for operating a carriage, comprising a support, a nut assemblyrotatably mounted on said support While restrained from axial movement,reversible power means operatively connected to a member of said nutassembly to rotate the same, a threaded shaft extending through said nutassembly in threaded engagement therewith and supported thereby, aU-shaped bracket rigid with said carriage, one end of said shaft beingpointed and engaging one leg of said bracketfor operative contact whenthe shaft and carriage are moved in one direction, abutment meanscarried by the shaft and engaging the other leg of said bracket foroperative contact when the shaft and carriage are moved in the oppositedirection, and releasable latch means mounted on the bracket, engageablewith means on the shaft to prevent rotation of the latter.

6. A carriage actuating mechanism, comprising a frame, an antifrictionnut assembly rotatably mounted on said frame while restrained againstaxial movement, reversible power means for rotating one member of saidassembly, a threaded shaft passing through and supported by saidassembly in threaded engagement therewith, one

end of said shaft being formed with a pointed end and a circumferentialgroove adjacent the pointed end for operative connection with saidcarriage to advance or retract the same, said connection comprising aU-shaped spring clip secured at its bight to said carriage, the freeends of the legs of said clip being formed with inturned tips forengagement in the groove of said shaft, and manipulatable means bridgingsaid legs for bringing said tips into clamping engagement in saidgroove, said last-named means including a recessed portion for abutingthe pointed end of said shaft.

7. Carriage-actuator mechanism comprising a support, a nut assemblycomprising an elongate ring member formed with spaced raceways on itsinner wall, bearing elements, each element having spaced toroidalportions operating in said raceways, a tubular cage within said ringhaving openings receiving said bearing elements, means rotatablymounting said ring on said support while restrained from axial movement,reversible power means operatively connected to the ring of said nutassembly to rotate the same, a threaded shaft extending through said nutassembly in threaded engagement with said hearing elements, meansconnecting one end of said shaft to said carriage for exerting push orpull thrust upon said carriage as the output of the motor is rotated inone direction or the other, releasable latch means for locking the shaftagainst rotation, a tubular housing mounted to receive the free end ofsaid shaft, and an abutment secured to said shaft near each end thereofand on opposite sides of said nut assembly, the abutment within saidtubular housing being in sliding contact therewith to steady said shaft.

8. Power-operated mechanism for moving a carriage back and forthcomprising a framework, means mounting an antifriction nut assembly onsaid framework, said means including a dished metal stamping,vibration-damping means connecting peripheral portions of said stampingto said framework, the central portion of said stamping being formedwith an opening and a flange portion extending outwardly from saidopening, a holder se cured to said stamping, said holder having anopening therethrough aligned with said flange, a sleeve fitted in theopening of said holder, said sleeve having a flange abutting said holderto limit its movement in one direction while engaging said stamping tolimit its movement in the opposite direction, an antifriction nutassembly including an outer ring disposed in said sleeve, said ringhaving a flange engaging said sleeve to limit its movement in onedirection while restrained by said stamping from moving in the oppositedirection, a threaded shaft passing through said nut assembly, one endof said shaft being rotatably connected to said carriage, a tubularhousing receiving the opposite end of said shaft, said housing beingmounted in said flange of said stamping, power means for rotating thenut assembly, and readily releasable means for locking said shaftagainst rotation.

9. Mechanism for operating a reciprocable carriage or the likecomprising a reciprocable shaft operatively connected with saidcarriage, power-driven nut means drivingly connected to said shaft formoving said shaft and carriage, and readily releasable latch meansconnecting said shaft and carriage against relative axial and rotationalmovement, whereby release of said latch means permits the carriage to bemanually moved relative to said'

